Touch panel having press detection function and pressure sensitive sensor for the touch panel

• US 8,094,134 B2
• Filed: 12/24/2009
• Issued: 01/10/2012
• Est. Priority Date: 12/25/2008
• Status: Expired due to Fees

• Current Assignee: Nissha Printing Company Limited (Nissha Co., Ltd.)
• Original Assignee: Nissha Printing Company Limited (Nissha Co., Ltd.)
• Inventors: Suzuki, Takahiro, Kai, Yoshihiro, Endo, Yuko, Takai, Yuichiro, Shimizu, Jun, Yamaoka, Yoshitaka, Okumura, Shuzo, Hirai, Seiko, Imai, Yohko
• Primary Examiner(s): Shalwala, Bipin
• Assistant Examiner(s): HOLTON, STEVEN E
• Application Number:
  US13/054,624
• Publication Number:
  US 20110115738A1
• Time in Patent Office: 747 Days
• Field of Search: 345173-178, 178 1801- 1811
• US Class Current: 345/173
• CPC Class Codes: G01L 1/205 using distributed sensing elements
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

An object of the present invention is to provide a touch panel having a press detection function, which makes it possible to suppress degradation of visibility of a display unit of a display device even when mounted on an electronic device, and also to improve a pressure measuring precision. For this purpose, the touch panel of the present invention includes a first substrate, a second substrate disposed oppose to the first substrate, a pair of electrodes disposed on either one of opposed surfaces of the respective substrates or disposed separately on both of the surfaces, pressure sensitive ink members disposed with a gap from at least one of the pair of electrodes, each of the pressure sensitive ink members having an electrical characteristic varied by a pressing force applied thereto, and a gap retaining member for bonding the first and second substrates to each other and for retaining a gap between each of the pressure sensitive inks and at least one of the pair of electrodes, wherein the pair of electrodes are disposed in a frame shape along an edge portion of the first or second substrate, and the pressure sensitive ink members are scattered along the edge portion of the first or second substrate so that, when the first or second substrate is deformed upon an application of an external force, at least one of them is made in contact with both of the pair of electrodes so as to make the two electrodes conductive to each other.

Claims

1. A touch panel having a press detection function, said touch panel comprising:

a pressure sensitive sensor for said touch panel, wherein

said pressure sensitive sensor for said touch panel includes;

a first substrate having a surface;

a second substrate having a surface and being disposed so as to be opposed to said first substrate;

a pair of electrodes disposed on one of said surface of said first substrate opposed to said second substrate and said surface of said second substrate opposed to said first substrate, or disposed separately on both of said surfaces;

pressure sensitive ink members having a conductive property of which an electric characteristic is varied by a pressing force applied thereto, each pressure sensitive ink member of said pressure sensitive ink members being disposed on said surface of said first substrate opposed to said second substrate or said surface of said second substrate opposed to said first substrate with a gap interposed from at least one of said pair of electrodes; and

a gap retaining member disposed on an opposed area between said first substrate and said second substrate, said gap retaining member having a sticking property such that said first substrate and said second substrate are bonded to each other and retain the gap between each of said pressure sensitive ink members and said at least one of said pair of electrodes,

said pair of electrodes are respectively disposed in a frame shape along an edge portion of said first or second substrate,

said pressure sensitive ink members are located in a scattered manner along said edge portion of said first substrate or said second substrate, and disposed so that when, upon application of an external force in a thickness direction of said first substrate, said first substrate or said second substrate is deformed, said pressure sensitive ink member is put in contact with both of said pair of electrodes so that said pair of electrodes are made to be conductive to each other,

said gap retaining member is disposed so as to cover at least one of said pair of electrodes located between said pressure sensitive members adjacent to each other when viewed in the thickness direction of said first substrate.

2. The touch panel having a press detection function according to claim 1, wherein said gap retaining member is double-sided sticky tape with a sticky agent being applied onto two surfaces of a core member.

3. The touch panel having a press detection function according to claim 1, wherein said pressure sensitive ink members are dots disposed on a plurality of corners of said first substrate or said second substrate.

4. The touch panel having a press detection function according to claim 1, wherein each of said first substrate and said second substrate has a rectangular outer shape, and

said pressure sensitive ink members have a broken line shape along only each of edge portions of paired longer sides of said first substrate or said second substrate.

5. The touch panel having a press detection function according to claim 1, wherein said pressure sensitive ink members are disposed at a pitch in a range of from 9.75 mm to 25.75 mm.

6. The touch panel having a press detection function according to claim 1, wherein each of said first substrate, said second substrate, and said gap retaining member has a frame shape.

7. The touch panel having a press detection function according to claim 1, wherein each of said first substrate and said second substrate is a transparent material having a flat plate shape, with a transparent window portion on a portion without said pair of electrodes disposed therein.

8. The touch panel having a press detection function according to claim 7, wherein a transparent electromagnetic shielding member is disposed on said first substrate or said second substrate so as to include said transparent window portion.

9. The touch panel having a press detection function according to claim 7, wherein said second substrate has a transparent electrode formed on said transparent window portion of said surface opposed to said first substrate into a stripe pattern in one direction.

10. The touch panel having a press detection function according to claim 9, wherein a third substrate is stacked on a surface of said second substrate on a side without said pair of electrodes formed thereon, with a sticky agent interposed therebetween, and

said third substrate is a transparent material having a flat plate shape, and has a transparent electrode disposed on an area corresponding to said transparent window portion of said surface opposed to said second substrate into a stripe pattern in a direction crossing the one direction.

11. The touch panel having a press detection function according to claim 1, further comprising:

a supporting member stacked and disposed on at least one of said surface of said first substrate and said surface of said second substrate on a side without said pair of electrodes disposed thereon.

12. The touch panel having a press detection function according to claim 11, wherein said supporting member is on a rear side of a position where said pressure sensitive ink member is disposed.

13. The touch panel having a press detection function according to claim 1, wherein

one of said pair of electrodes is disposed on said first substrate,

an other one of said pair of electrodes is disposed on said second substrate, and

said pressure sensitive ink members are provided to cover a plurality of portions of said one or said other one of said pair of electrodes.

14. The touch panel having a press detection function according to claim 13, wherein each electrode of said pair of electrodes are covered with either one of said pressure sensitive ink member or said gap retaining member.

15. The touch panel having a press detection function according to claim 1, wherein

said pair of electrodes are disposed on said first substrate with a gap therebetween, and

said pressure sensitive ink members are disposed on said second substrate.

16. A pressure sensitive sensor for a touch panel comprising:

a first substrate having a surface;

a second substrate having a surface and being disposed so as to be opposed to said first substrate;

a pair of electrodes disposed on one of said surface of said first substrate opposed to said second substrate and said surface of said second substrate opposed to said first substrate, or disposed separately on both of said surfaces;

pressure sensitive ink members having a conductive property of which an electric characteristic is varied by a pressing force applied thereto, each pressure sensitive ink member of said pressure sensitive ink members being disposed on said surface of said first substrate opposed to said second substrate or said surface of said second substrate opposed to said first substrate with a gap interposed between at least one of said pair of electrodes; and

a gap retaining member disposed on an opposed area between said first substrate and said second substrate, said gap retaining member having a sticking property such that said first substrate and said second substrate are bonded to each other and retain the gap between each of said pressure sensitive ink members and said at least one of said pair of electrodes,

said pair of electrodes are respectively disposed in a frame shape along an edge portion of the first or second substrate,

said pressure sensitive ink members are located in a scattered manner along said edge portion of said first substrate or said second substrate, and disposed so that when, upon application of an external force in a thickness direction of said first substrate, said first substrate or said second substrate is deformed, said pressure sensitive ink member is put in contact with both of said pair of electrodes so that said pair of electrodes are made to be conductive to each other,

said gap retaining member is disposed so as to cover at least one of said pair of electrodes located between said pressure sensitive members adjacent to each other when viewed in the thickness direction of said first substrate.